*Another day, another chapter in the sordid Montana Fishburne saga.

E! News is now reporting that Laurence Fishburne’s daughter is being investigated for allegedly handing her boyfriend’s ex-girlfriend a vicious beatdown.

The budding porn star was arrested in February and accused of breaking into the home of the victim, forcing her into a bathroom and beating her repeatedly. She pleaded not guilty to simple battery and false imprisonment.

But prosecutors told E! they’re working on additional charges as well, including assault with a deadly weapon and trespassing.

…Also, Montana Fishburne is now lawyered up with Lindsay Lohan’s attorney, Shawn Chapman Holley.